The former Education Secretary said it was a "tragedy" that a "uniquely clear moral moment" for Britain had been tainted by those who questioned whether refugees had lied about their age.

It comes after David Davies, the Conservative MP for Monmouth, called for dental investigations or X-rays for refugees coming to the UK.

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The Home Office has ruled out the suggestion, saying it was "inaccurate, inappropriate and unethical".

On Wednesday Mr Davies was accused in the House of Commons of fuelling "xenophobic attacks" after he said the teenagers "don't look like children".

He was also criticised by the British Dental Association, but he said he did not accept that it was "intrusive" to take an X-ray of a migrant.

Orphaned refugee children walking amongst the shelters at the Jungle camp at CalaisCredit:
Chris Radburn/PA Wire

Mrs Mogran said: "When we’ve had a uniquely clear moral moment for this country, it’s a real tragedy to see it tainted by a few loud and frankly thoughtless individuals who do not think we’ve found the right kind of children.

"These children come from some of the most difficult and unsafe parts of the world. In many cases they haven’t known safety, security, or trust.

"I’m afraid this is part of a bigger debate, which is clouded by misinformation, poor judgement and some very unpleasant rhetoric which is gaining ground in this country."

Nicky MorganCredit:
Julian Andrews

She added that the last thing these children need at this traumatic time is an" intrusive, inaccurate and unnecessary medical examination."

While she said it was reassuring to see the Home Office confirm that these sorts of checks will not be carried out, the Conservative MP said they could be doing more to "calm" any doubts about the existing checks.

Mrs Morgan called on Britain to "do the right thing" and to remember that the refugee crisis doesn’t end with the bulldozers in Calais.

Lily Caprani, Unicef UK’s Deputy Executive Director, said: “At a time when the UK has shown real humanity and a commitment to respecting the rights of children searching for safety, it’s a great shame that a vocal few are now questioning their right to be here.

"Forcing traumatised children to undergo dental and medical checks to determine their ages would be intrusive, inaccurate and, frankly, cruel. The Home Office is right to have ruled this out."